Multiphoton curing processes are described in U.S. Pat. No. 6,855,478. In these processes, a layer of a multiphoton curable photoreactive composition is applied on a substrate and selectively cured using a focused source of radiant energy, such as an ultrafast laser beam. A multiphoton curing technique may be used to fabricate two-dimensional (2D) and/or three-dimensional (3D) structures with micro- or nano-scale resolution.
Using a multiphoton curing technique, a 3D structure may be constructed voxel-by-voxel (3D volume element by 3D volume element) by controlling a location of the focus of the laser beam in three dimensions (i.e., x-axis, y-axis, and z-axis directions) within the photoreactive composition. In many cases, 3D structures are formed by curing approximately single voxel layers (e.g., in the x-y plane), followed by moving the focal point about one voxel length (e.g., in the z-axis), and curing a subsequent layer (e.g., in the x-y plane). This process may be repeated until the desired structure is at least partially cured.